Improved capstan



UNITI-3D STATES ATENT Ormea,

ZEBULON ERASTUS OOFFIN, OF NEWTON CENTRE, ASSIGNOR TO HIMSELF, AND WILLIAM P. HUNT, OF BOSTON, MASSACHUSETTS.

iMPRoVEu CAPs-rau.

Specification forming part of Letters Patent No. 35,730, dated JUE@ 24, 185% To all whom t may concern:

Be it known that I, ZEBULON ERnsTUs Cor- FIN, of Newton Centre, in the county of Middlesex and State of Massachusetts, have invented a new and useful Improvement in that class of Oapstaus wherein the power is made variable by means of gears, pawls, 8mo.; and I do hereby declare that the following is a full and exact description thereof, reference being had to the accompanying drawings, and the letters of reference marked thereon, making part of this specification, in which* Figure l is a sectional elevation; Fig. 2, a plan with the lever-head removed. Fig. 3 is a View of the lever-head from beneath. Fig. 4 is a sectional plan of hollow shaft G, showing the expanded rim at the bottom and pawls G connected thereto.

Part A is a foundation-plate, in which is securely keyed the stationary spindle B. On the spindle B is fitted to turn freely a hollow shaft, O, and to the arrangement of this hollow shaft, in connection with other parts, my vinvention relates. The lower end of shaft O is expanded, forming a large strong rim to carry the pawls G, and on the foundation plate are suitable corresponding ratchet-teeth, H. On the exterior' ofthe hollow shaft O the capstan-barrel F hasits bearing for rotation when operating with its slow powerful motion, and the fitting is made free and suitable accordingly. The barrel F is furnished with pawls D, which are arranged to act upon corresponding ratchet-teeth, E, in the foundationplate A, whenever t-h'e capstan is operated with either the simple or powerful motion, to hold thel barrel from turning back.

J is the lever-head, in which is made fast the pinion K, which is fitted to turn freely on the fixed spindle B. The pinion K thus forms a bearing for and carries the head. The leverhead J is furnished with paivls L, arranged to act on a corresponding series of ratchet-teeth, M, and drive the capstan-barrel for the simple motion.

N is a ring and series of inclines furnished with knob O, by which to move them, and they serve to lift the pawls L out of action when it is desired to turn the capstanbarrel backward without turning the head.

The top of the hollow shaft O is enlarged suitably to carry the studs P, and on these .studs are placed the intermediate gears, Q,

which mesh into the pinion K, and also into an internal gear, R, fixed in the top of the capstan-barrel. The parts are made of such suitable materials as are usually employed in the art.

The operation is thus: Levers being applied to the sockets in head J, and the head turned around to the left, the pawls L take in ratchetteeth M and the capstan barrel is driven as a simple capstan, the hollow shaft and other parts finding and turning upon the smallest bearing where is least friction-viz., on the fixed spindle B. When the more powerful motion is required, the direction of motion of the lever-head is reversed, when the pinion K drives intermediates Q, whose stud-hearings now become stationary by the pawls G taking ou ratchet-teeth H, and they then drive the capstan-barrel with a slow and powerful motion in the same direction as with the simple mot-ion by acting on the internal gear, E, the pawls D holding the barrel from turning back in both cases. The introduction of the hollow shaft in this manner secures important advantages. It secures the advantage of making the spindle or main central shaft a fixture, while it furnishes superior facility for stability and strength in the supporting and` carrying of the intermediates Q and pawls G, and the central shaft or spindle being fixed can be made smaller than when required to turn in its socket. The wear also is taken upon an increased length of surface and without liability to bind, while the Wear during the powerful motion is transferred to the exterior of the hollow shaft.

I do not wish to claim any ofthe parts separately; but, believing that the introduction of the hollow shaft O, with its appendages and relations to the several parts as here shown, to be novel and peculiarly advantageous,

Vhat I claim as my invention, and desire to secure by Letters Patent, is-

The arrangement of the hollow shaft O within the capstan-barrel and upon the fixed spindie B, said hollow shaft being arranged to carry the gears Q above and the pawls G upon an expanded rim at the bottom, and so as to freely turn upon the fixed spindle for the simple motion, but becoming stationary when the gears are brought into action by reversing the motion of the lever-head, substantially as and for the purposes set forth.

ZEBULON ERASTUS COFFIN. Vitnesses:

F. W. HURD, D. N. B. COFFIN, Jr. 

